(1) Field of the Invention
The present invention pertains to a blower housing that may be used with a climate control furnace or a water heater. The blower housing provides cooling of the motor that rotates the blower fan and provides dilution and cooling of exhaust gases drawn from the furnace or water heater. The housing is constructed of only two pieces in one embodiment, and five pieces in a second embodiment, and is designed to be easily mounted to a flat surface of the furnace or water heater.
(2) Description of the Related Art
Home or office furnaces and/or water heaters typically include a blower that operates to draw ambient air into the combustion chamber of the furnace or water heater and to expel exhaust gases or fumes from the furnace or water heater through an exhaust pipe or chimney. The typical blower includes a blower housing having a volute shape and a radial fan or a squirrel cage fan mounted in the blower housing. The blower housing has an inlet vent opening at its center communicating with the center of the fan and an outlet exhaust opening at the periphery of the volute shape communicating with the exhaust pipe or chimney. An electric motor is mounted to the blower housing on an opposite side of the housing from the inlet vent opening. The motor rotates the fan to cause the fan to draw exhaust gases and fumes into the center of the fan in the blower housing through the inlet vent opening and exhaust the gases and fumes from the housing through the outlet exhaust opening.
In use of the typical blower with a typical furnace, the inlet vent opening of the housing communicates with an outlet of the furnace heat exchanger. On operation of the blower motor and rotation of the blower fan, a vacuum is created by the fan in the blower housing that draws ambient air into the combustion chamber of the furnace where it mixes with the gas or other fuel combusted in the combustion chamber. The hot combustion gases and fumes produced by the combustion chamber are then drawn through the heat exchanger of the furnace by the blower. The blower fan draws the combustion gases and fumes from the heat exchanger into the blower housing and expels the combustion gases and fumes through the exhaust pipe or chimney communicating with the exhaust outlet of the blower housing.
The typical operation of the blower employed with a water heater is similar to that of the furnace. On operation of the blower, ambient air is drawn into the combustion chamber where it mixes with the gas or other fuel being combusted. The combustion gases and fumes are then drawn through the heat exchanger of the water heater where they heat the water contained in the heater. The combustion gases and fumes are then drawn from the heat exchanger and through the blower housing and are expelled through the exhaust pipe or chimney by the blower.
Improvements in the typical blower used with a furnace or a water heater have included modifications to the blower housing where rotation of the fan not only draws the combustion gases and fumes from the heat exchanger of the furnace or water heater into the housing before being expelled, but the fan also draws a flow of cooling air over the motor rotating the fan to cool the motor. Modifications to the blower housing have also enabled ambient air to be drawn directly into the blower housing to mix with the heated exhaust gases and fumes drawn into the blower housing to dilute and cool the exhaust gases and fumes with the ambient air prior to their being expelled through the exhaust pipe or chimney communicating with the blower housing. However, these modifications to the typical blower housing have complicated the constructions of the blower housing which increases their manufacturing cost. In addition, the modifications to the typical blower housing have also complicated the assembly of the blower housing to the furnace or water heater with which it is used, resulting in increasing the time required to assemble the housing to the furnace or water heater and thereby increasing the assembly cost of the furnace or water heater. Still further, providing an opening in the blower housing to enable ambient air to be drawn directly into the housing to mix with the heated exhaust gases and fumes to cool the exhaust gases and fumes also enables the noise of operation of the motor and fan to escape from the blower housing. A person's fingers could also be inserted through the opening and come into contact with the moving parts of the motor, causing injury to the person's fingers. The heated exhaust gases and fumes drawn into the blower housing also heat up the portion of the blower housing that directs the gases and fumes into the fan. A person's hand contacting this portion of the blower housing could result in serious burns to the hand.
What is needed to overcome these disadvantages of prior art blower housings used with climate control furnaces and water heaters is a blower housing that provides the benefits of motor cooling and exhaust gas dilution and cooling in a simplified, inexpensive blower housing that is easily assembled to the furnace or water heater with which it is used. The blower housing would also include safety features that would guard against a person inserting their fingers through the opening in the blower housing provided for ambient air and would also insulate portions of the blower housing to prevent a person's hand from being burned when contacting the exterior surface of the blower housing. The blower housing construction would also reduce the noise of motor and fan operation transmitted through the ambient air opening of the housing.